Safety lock



Aug. 24, 1965 YEAGER 3,201,959

SAFETY LOCK Filed Sept. 4, 1962 2 Sheets-Sheet 1 7 FIG. 3

INVENTOR'. Bovp H. YEAGE-R BY M y ATTORNEYS 1965 B. H. YEAGER 3,201,959

SAFETY LOCK Filed Sept. 4, 1962 2 Sheets-Sheet 2 INVENTOR. Bow: H. YEAGER ATTORNEYS United States Patent 3,201,959 SAFETY LQCK Boyd Henry Yeager, Byron, Mich, assignor to The Engineered Products Company, Flint, Mich, a corporation of Michigan Filed Sept. 4, 1962, Ser. No. 221,061 11 Claims. (Cl. 7tl134) This invention relates to locking mechanisms and in particular to a key actuated safety lock. In prior art locking mechanisms of the type having a lock bolt that engages a keeper, when the lock bolt is only partially extended within the keeper the bolt can be jimmied easier than when thebolt is positively retained in a fully extend-ed locked position within the keeper.

Therefore, the primary objects of this invention are to provide a safety lock that has positive lock and unlock positions and that prevents withdrawing a key from the lock once the locking operation has been initiated until the locking operation has been completed or the lock is returned to an unlocked condition.

In the drawings:

FIG. 1 is a fragmentary view showing an exemplary use of the lock on a door with the lock bolt fully extended into engagement with a keeper.

FIG. 2 is a cross section taken along the lines 22 of FIG. 1 and shows a portion of the locking mechanism that provides positive locked and unlocked positions for the mechanism.

1 16.3 is a cross section taken along the lines 33 of FIG. 2 to illustrate the condition of the mechanism at the completion of a locking operation. FIG. 4 is .a' cross section taken along the lines 4 i of FIG. 3.

FIG. 5 is similar to PEG. 3 but shows the locking mechanism when the key is moved toward the withdrawal position before the locking operation has been completed. FIG. 6 shows a view taken along lines 6-6 of FIG. 3 to illustrate a slidable fulcrum that is. incorporated in the instant locking mechanism.

PEG. 7 is a perspective view showing the details of the lock bolt.

FIG. 8 is a perspective view of a safety hinge included in the actuating mechanism for the lock bolt.

' FIG, 9 is a view showing an arrangement for locking the tumbler cylinder against rotation.

As shown in FIG. I, lock it? may be positioned at the bottom edge of glass door .12 on metal door frame 11 at a point remote from hinge 14 by bracket 13 as is common in commercial installations. Lock 1% has a lock bolt 16, a case 2d, and a tumbler cylinder 22 threaded in the case. Look bolt 16 extends vertically downward to register with a slot in a keeper 1%. Tumbler cylinder 22 is operated by a key 24.

The mechanism for shifting look bolt 16 to and from locked and unlocked positions generally comprises guide blocks 26, 28, a pivotal and axially shit-table lever 34, fulcrum block 56, pivotal dog 68 and safety hinge 62.

Lover 34 is operatively connected to lock bolt 16 by a 'pin 36 which is secured between the branches of the lbifurcate end 38 of lock bolt 16 (FIG. 7) and passes through an axial camrning slot all in lever 34. A compression spring 40; is positioned in slot 49, between one end thereof and pin 36 so as to urge lever 34 toward the left as viewed in FIGS. 3 and 5. lever 34 has rollers 48 rotatably supported o-none end thereof, the other end passing through a slot 54 of fulcrum block 56 (FIG. 6) so as'to be fulcmmed at the ends of slot 54 and axially slidable within the slot. Fulcrum block 56 is supported for limited movement on case 20 by a pin 58 and slot 60 arrangement to change the fulcrum point of the lever during locking and unlocking operations.

Lock bolt 16 is axially slidable on guide blocks 26, 28 which are secured to case 26 by pins 30, 32. Guide blocks 26, 28 are suitably .apertu red longitudinally at 27 to accommodate one end of lever 34 for movement therein. Transverse grooves 44, 46 in guide blocks 26, 28 are adapted to receive rollers 48 and serve as stop positions for the pivotal movement of lever 34 corresponding to locked and unlocked positions, respectively, of lock bolt 16. Grooves 44, 46 have inclined side walls 50, 5-2 that cam rollers 48 out of grooves 34, 46' onto shoulders 47 of guide blocks 26, 28 to shift lever 34 axially when lever 34 is pivoted by rotating dog 68 against safety hinge 62. Dog 68 rotates about axis 69 in response to rotation of key 24. Key 24 can be inserted into and withdrawn from tumbler cylinder 22 only when dog 68 is positioned as shown in full lines in FIG. 3. Hinge 62 includes boss 66, flat flocking extension 70, inclined locking extension 71, upturned flange 72 and unlocking extension 73 (FIG. 8). One end of hinge 62 is bifurcated to accommodate lever 34 between the branches thereof. Pin 64 is journalled through boss 66 and passes through lever 34 to pivotally connect hinge 62 to lever 34. Flat locking extension 70 is inciined to inclined locking extension 71 at about 15 degrees, flange 712 being bent at a right angle toinclined locking extension 71. When dog 68 is rota-ted clockwise, from the position shown in full lines in the direction of the arrows in FIG. 3, the dog engages the boss 66 and flat extension 79 of hinge 62 to pivot lever 34 clockwise as viewed in FIG. 3 about the end of slot 54 in the fulcrum block 56.

Lock bolt 16 has a spring biased detent 74 urged outwardly from the lock bolt by compression spring 76. When lever 34 is shifted to the right as shown in FIG. 5, rollers 48 resting on shoulders 47, detent 74 engages extensions 70, 7d of hinge 62 to pivot hinge 62 counterclockwise about pin 64. So long as rollers 48 rest on shoulders 47, detent 74 yieldably maintains hinge 6'2 positioned so that flange 72 will engage dog 68 if it is rotated counterclockwise by movement of the key toward its Withdrawal position. However, when rollers 48 rest in either groove 44 or 46 so that lever 34 is shifted to the left, detent 74 does not maintain flange 72 in .a position to engage dog 6S,

FIG. 9 shows another safety feature of the lock for preventing removal of the tumbler cylinder 22 after the safety lock has been enclosed within the metal door frame 1 1. A latch lever 78 is pivotally connected to case 20 by a screw 8t} and has an elbow 82 having an inclined edge 34 engaged by set screw 86 to look right angle corner 8'8 into one of the V-shaped grooves 90 on the tumbler cylinder 22.

With the locking mechanism in its unlocked condition, key 24- may be inserted into and withdrawn from tumbler cylinder 22 when pivotal dog 68 is positioned in a neutral or withdrawal position as shown in full lines in FIG. 3. Rollers 48 are positioned in groove 44 so that lever 34 is shifted to the left as viewed in FIGS. 3 and 5 and lock bolt 16 is fully withdrawn into case 20. The locking operation is initiated by inserting key 24 into tumbler cylinder 22 and rotating the key so that dog 63 rotates clockwise, in the direction of the arrows in FIG. 3, into engagement with boss 66 and flat locking extension 70 of safety hinge 62. During this initial rotation detent 74 does not engage hinge 62, lever 34 being shifted to the left, so that dog 68 is free to rotate past flange 72 or if it engages flange 72, flange 72 will pivot so that .3 dog 68 can move into the aforementioned engagement with boss 66 and flat locking extension 70. After dog 68 engages hinge 62, continued clockwise rotationof the dog shifts fulcrum block 56 downward asviewedin FIG. 3 and lever 34 begins to pivot clockwise about the lower end of slot 54. Pivotal movement of lever 34.cams roll- 3. .A'locking mechanism as set forth in claim 2 wherein said yieldable means is a spring biaseddetent carried by said lock bolt so as to contact said safety hinge when said lock bolt is intermediate its locked and unlocked posiers 480m of groove 44on inclined side wall 50 against the action of spring.42.j When rollers 48 have moved out .of groove 44 and rest on shoulder 47,"lever 34 has i V shifted to the right as shown in FIG. 5. With lever 34 shifted to theright, detent 74 pivots'safety hinge 6,2"

counterclockwise about pin164, moving flange 72 .into' a position .to positively engage dog 68'if one attempts to rotate 'the key counterclockwise to the key-withdrawal position while the mechanism is in a, partially locked position. Detent74 will yieldably maintain flange 72 in this position relative to dog 68 untillever 34 is shifted to the right as rollers 48 drop into groove'4 6. FIGLS shows the locking mechanism inan intermediate position, dog 68 having .beenrotated counterclockwise toward the key withdrawal position without having first com z pleted the locking operation. With flange 72 engaging dog 68 the locking mechanism must be returned to its unlocked condition before. the key' can be withdrawn from the tumbler cylinder '22. L

tions. Y Y

4. A locking mechanism asset forth in claim 2 wherein said actuating means is 'afrotatable dog and said hinge comprises a boss'anda locking extension, said boss being pivoted to'said lever, said extension having an upturned flange remote from said boss, said dog being adapted to engage said boss ,.to pivot and thereby axially shift said lever, and said yieldable means being adapted to engage said locking extension when said .leveris shifted axially.

v 5. A'lockingimechanism' having locked andunlocked positions comprising a frame,-an aXially shiftable lock bolt, a lever operatively'connected' to said bolt to shift said bolt to'and from, said lockedand unlocked positions, said lever being pivotableand axially shiftable stop means .for limiting pivotal movement of said lever when said bolt is in alocked or unlocked position, said stop means comprising apair of grooves in said frame, 'said grooves corresponding to "said lockedand unlocked position, said 7 I leverha'ving'an abutmentat one end thereof-positidnable Referring again to the locking operation, after rollers 48 have moved out of groove 44-against theiaction of 1 spring/$2, continued clockwise rotationof dog 68 pivots lever '34 clockwise until rollers 48'reach transverse groove 46 whichcorresponds tothe locked position of lock bolt 16. Spring .42 moves lever 34 axiallyto the left, pulling rollers 48'into groove 46 as lever. 34 shifts to the left] As lever. 34 shifts to the left,'hinge 62 moves outofj engagement with'detent '74 and ,hinge'62 is pivoted clock wise by the outermost portion of' the1dog'68,'positioned 1 within said grooves, actuating means for pivoting said lever to move said lockbolt between said lockedand un locked positions, and meansre'sponsive to pivoting of said lever for shifting'said lever axially intoand out of 'said grooves.

' 6. A locking mechanismfas setlforth in claim 5wherein said lever shifting means comprises aside wall of each of said grooves, said side walls being inclined toward the other of said grooves whereby when said lever is pivotedsaid inclined side, walls c'am said abutment out of" said as shown in'broken lines in *FIG.,3, to retract upturned.

flange 72 so that dog 68 may berrotated freely to the key I withdrawal." The unlocking'operation is similar to'the locking operationrinthat counterclockwise rotation of dog 6811s viewed in FIG. 3 causes the dog to engage.

unlocking extension '73 andboss 66 to shift fulcrumblock 56upward1as' viewed in FIG. 3, pivot' lever 34 counter- 'clockwiseland move rollers 48, outof groove 46-into 'I claim: v i r 1. A locking mechanismcomprising a lock bolt movable from an unlocked position to a'locked position, a

pivotal and axially shiftable lever operatively. connected to said lock bolt to move saidfbolt'from said unlocked position vtosaidlocked position, rotatable actuating means for'pivoting said lever when said actuating means is ro'rv i tated from a neutral position toward alockedposition,

meansresponsive topivotal movement of the lever for shifting said lever axially and maintaining said lever in V Qsaid shiftedposition when ;said lock bolt, is'intermediate its'locked and unlocked positions,;andsafety' neans reposition from saidlockedposition and said lock bOlt'lS positioned intermediate said locked and unlockedposi+ "sponsive to the axial [shifting of: said leverand adapted,- 7 to engage said rotatable actuating meansWllQn said actuating means is rotated in a.direction towards said neutral,

grooves to shift said lever axially.

' 7.. Alocking mechanism as ,set forth in claim 5 further comprising springmeans" for urging said abutment in a direction toward" the bottom-of said grooves.

8. A locking mechanism as setf orth in: claimS whereia saidlock'bolt has a birurcate and for accommodating saidlever between the branches thereof,'saidlever has an axial slot,"saidbifurcate end being operatively connected -to said lever by "a pin extending between saidjbranches andth'roughsaid slot, and aspring carried in said slot be tween one endfo'f said slot and said pinto urge said abutment in a'direction toward the bottom of said grooves. J 9. -A- locking mechanism as set forth in claim 5 wherein said frafne'includes a'guideblock, said lock bolt being axially. slidableon one surface of said block, said block having an aperture the'rethro'ugh to accommodate one end of said leverfor movement-in saidv block .when said lever is pivoted, said aperture communicating between said one surface and an opposite surface of said block, said grooves extending inwardly of said block from said opposite surface, said grooves further being/transverse to and spaced along said aperture. p p 7 10., A locking mechanism having locked andunlocked positions comprising a frame, an axially shiftable lock bolt, a lever operatively connected adjacent one end thereof to. said bolt, said lever being pivotableand axially shiftable, a fulcrum block carried by said frame for limited shiftablemiovement 'withirespect thereto, said fulcrum said safety means comprisesa safetyhinge 'and'yieldablej a means, said hinge being pivoted onsaid 'lever. and said yieldable' means being'adapted to engage said hinge when said leveris shifted 'axiallywhereby when said leveris shifted axially said 'yieldable means pivots said safety :hinge' so'ithat said hinge engages saidactuating means if .said actuating means is rotated towards said neutral posi-I 1 --tion when said lock bolt is intermediate said locked: and

unlocked positions. 9 M

V unlo'cking operations. .1. v 70 blockrhaving a slot to.,accommodate the other end of said lever. for movement therein; each endof said slot "comprisinga fulcrum point. for pivotal m ovement of said lever, and actuating means forpivoting said lever and, shifting saidlever axially,=whereby When said lever is pivoted by said actuating meanslsaid fulcrum block shifts ,to 'changefthe fulcrumpoint during; locking and 11. In combination a key,j'a key actuated lock; said key being removable. from s aidllock when"said key-is in a 'predetermined position with. respect to said lock, a lock bolt, lock bolt actuating iineans forgmoving, said bolt -;from anunlocked to alocked position in response to rotation of said key in 'a first direction from said predetermined position to a second position corresponding to said locked position of said bolt, and means operable once a locking operation has been initiated for preventing said lock bolt from. being positioned intermediate its locked and unlocked positions when said key is rotated in an opposite direction without having first completed said locking operation, said key being freely rotatable in said opposite direction to said predetermined position after a locking operation has been completed while said lock bolt remains in said locked position.

References Cited by the Examiner UNITED STATES PATENTS 335,024 1/86 Felinlee 292143 5 2,083,796 6/37 Schlage 70134 2,522,878 9/50 Larson 292143 2,780,088 2/57 Nabeit 70134 3,011,817 12/61 Eads 292-140 10 ALBERT H. KAMPE, Primary Examiner. 

11. IN COMBINATION A KEY, A KEY ACTUATED LOCK, SAID KEY BEING REMOVABLE FROM SAID LOCK WHEN SAID KEY IS IN A PREDETERMINED POSITION WITH RESPECT TO SAID LOCK, A LOCK BOLT, LOCCK BOLT ACTUATING MEANS FOR MOVING SAID BOLT FROM AN UNLOCKED TO A LOCKED POSITION IN RESPONSE TO ROTATION OF SAID KEY IN A FIRST DIRECTION FROM SAID PREDETERMINED POSITION TO A SECOND POSTIION CORRESPONDING TO SAID LOCKED POSITION OF SAID BOLT, AND MEANS OPERABLE ONCE A LOCKING OPERATION HAS BEEN INITIATED FOR PREVENTING SAID LOCK BOLT FROM BEING POSITION INTERMEDIATE ITS LOCKED AND UNLOCKED POSITIONS WHEN SAID KEY IS ROTATED IN AN OPPOSITE DIRECTION WITHOUT HAVING FIRST COMPLETED SAID LOCKING OPERATION, SAID KEY BEING FREELY ROTATABLE IN SAID OPPOSITE DIRECTION TO SAID PREDETERMINED POSITIONN AFTER A LOCKING OPERATION HAS BEEN COMPLETED WHILE SAID LOCK BOLTS REMAINS IN SAID LOCK POSITION. 